1. Field of the Invention
The invention relates to diagnostic tools for gas burners.
2. Description of the Related Art
There is a need to log events that occur during the operation of a gas burner when there is an intermittent problem that causes the gas burner primary control to cycle to a safety standby condition.
Presently, the only method for a repair technician to diagnose and repair such an intermittent problem is to replace one part of the gas burner system each time there is a malfunction.
Occasionally, proper operation of a gas burner is interrupted by an intermittent condition that causes the burner to go to a condition, variously called safety standby, safety lockout, or to "go out on safety." When this occurs, manual resetting of the gas burner primary control by either the resident or a service technician is required. This condition can be caused by a faulty part in the gas burner, a faulty gas burner primary control, fuel delivery problems, or an improperly operating igniter assembly.
When the service technician arrives, the intermittent condition causing the safety lockout may or may not be still present. The gas burner may operate satisfactorily for several days, only to go to a safety lockout again when the intermittent condition reoccurs. This frustrating sequence can occur several times as presently the only method of diagnosis and repair available is to replace one part after another and wait to see if the problem reoccurs again. This process can take several days or weeks and throughout this period, the resident of the property is unsure whether the heating system of the building is reliable and whether any absence coincidental to such an occurrence will result in significant damage to the building due to freezing conditions.
U.S. Pat. No. 5,063,527, issued to Price et al. on Nov. 5, 1991, discloses a monitoring system directed to controlling safety aspects of burners. This is done by referencing real time conditions relative to reference standards. The system does not disclose or suggest the need for monitoring an historical record of operation or the necessary structure to accomplish such monitoring or is suitable for use with low voltage on/off thermostats found on residential gas burners.
U.S. Pat. No. 5,249,739, issued to Bartels et al. on Oct. 5, 1993, discloses an apparatus for sensing the operating condition of a burner system. Bartels et al. teaches a temperature sensor mounting within the exhaust flue and providing a temperature signal encoding the temperature of the combustion gases within the flue. Bartels does not measure the outside of the flue pipe nor utilize a light sensitive cell to indicate burner status (on or off). Bartels et al. uses the measured temperature level of the actual flue gases to evaluate heating system performance including efficiency at various fuel firing rates. Bartels et al. teaches monitoring gradual changes in the flue gas temperatures.
U.S. Pat. No. 5,005,142, issued to Lipchak et al. on Apr. 2, 1991, discloses a sensor system for communicating to a control section which compares the signals to a standard and then sounds a warning if there is significant deviation.
A system that logs the data history of residential gas burners, accurately recording the history of events as they occurred so that the record can be viewed for diagnosis of the problem is not taught in the prior art.